Comment from All Nippon Airways (ANA)

Dear FAA AD Team, ANA requests the following modifications/clarifications for this NPRM. #1: Target the AD on the MFP, specifically to MFPs with a prior overhaul history The proposed AD is applicable to engines, and actions are required at the next engine shop visit. The unsafe condition is only related to past overhaul work performed on the MFPs. GE has clarified to operators that only MFPs with a prior overhaul history are affected by the SB. Furthermore, because the MFP is a Line Replaceable Unit, if the AD compliance trigger remains tied to the engine shop visit, affected MFPs could be rotated to other on-wing engines. We requests to change the applicability of this AD to target the MFP level, and to limit the affected group specifically to MFPs that have a prior overhaul history. #2: Clarify the Term "no prior service history" Paragraph (g)(2)(ii) defines an eligible part as a MFP with no prior service history. It can be interpreted as a MFP that has never been operated in flight. Since the unsafe condition is caused by the screw inadequately torqued during overhaul as GE told, newly manufactured pumps that have been operated but never repaired should be considered not affected. We requests to provide a clear definition of "no prior service history" to clarify that it means no overhaul history since its original manufacture. #3: Allow MFPs marked with "SB 73-0006" as eligible part for installation, and remove overhauled requirements Paragraph (g)(2) of the proposed AD defines a part eligible for installation. Specifically, paragraphs (g)(2)(iii) and (g)(2)(iv) require that the MFP must have been overhauled in addition to having all thrust bearing screws replaced. However, the referenced Woodward SB does not require an overhaul of the MFP but the thrust bearing screw replacement. We requests to revise paragraphs (g)(2)(iii) and (g)(2)(iv) to remove the overhauled requirement, and instead require only the thrust bearing screw replacement. Especially for paragraphs (g)(2)(iii), we request that any MFP marked with "SB 73-0006" on its SB plate be defined as a part eligible for installation. Thank you for considering our comments. Sincerely,